The research program consists of biochemical and morphological studies on the formation and removal of intracellular lipid deposits in rabbit arterial cells. Two projects are planned: 1) Cells freshly isolated from normal aorta will be used to develop differentiated, quiescent smooth muscle cell cultures which more closely reflect the physiologic state of arterial cells in situ. These cultures will be used for a general study of smooth muscle cell lipid metabolism. 2) Lipid-laden atheromatous cells isolated from diseased aortas will be placed in culture. Cholesterol trapping agents will be added and the cellular excretion of cholesterol followed. At the same time, changes in the lipid content, enzyme activity, and morphological appearance of the cells will be assessed.